Answer:

Step-by-step explanation:
The polynomial given for simplification is:

Now, we combine like terms using the commutative property of addition.
The commutative property of addition states that:

So, the order can be shuffled when we add terms.
The terms containing 't' are grouped together and the constant terms are grouped together. This gives,

Now, we group them using associative property and converse of distributive property as:

Simplifying the above expression, we get:

Therefore, the simplified form is 
-1.45923280296 is correct
Step-by-step explanation:

Well, plug in all the values.
(sqrt)3>3
False. 3 would be more than it's square root.
(sqrt)9>3
3>3
This is false. 3 is not bigger than 3. They are equal.
(sqrt)15>3
3.8729..... >3
That is true,
(sqrt)10>3
3.1622>3
This true.
-3 and 0 would not work either.
So,
"C" and "D" are correct solutions.
I hope this helps!
~kaikers
it's 21/21 which would simplify to 1
How I got that answer was by multiplying 3/7 and 7/3 to get 21 both times